As demand for reduction in size of a semiconductor device is increased, an imprint lithography technique is becoming popular. The imprint lithography technique is a nonconventional technique which forms a pattern by bringing a pattern formed on a mold into contact with an imprint material fed on a substrate (by impressing the pattern to the imprint material).
An optical imprint lithography method is described as an example of this imprint lithography technique. First, a layer made of photo-curable resin (hereinafter, imprint resin) is formed on a substrate (for example, a semiconductor wafer). Then, a mold having a desirable structure with fine relief pattern (a pattern) is brought into contact with the imprint resin. Then, the imprint resin is irradiated with ultraviolet rays and hence cured while the imprint resin is in contact with the mold. Thus, the pattern formed on the mold can be transferred to the imprint resin.
The imprint lithography apparatus performs alignment every shot before the mold is brought into contact with the imprint resin. For the alignment by the imprint lithography apparatus, a through-the-mold detection system (hereinafter, TTM detection system) has been used. The TTM detection system can perform alignment by simultaneously detecting marks formed on the mold and the wafer. Patent Literature (PTL) document 1 describes an imprint lithography apparatus in which an illumination system that irradiates a resin layer with ultraviolet rays from above the mold through the mold is arranged above the mold, and a TTM detection system is arranged in a manner that does not interfere with the illumination system.